This invention relates to a windshield wiper control system, and more particularly to such a system which is responsive to the speed of the vehicle.
In conditions where a light rain is falling on a windshield it is desirable that the vehicle windshield wipers operate intermittently. Otherwise, leaving the wipers on continuously may cause smearing and undue wear on the wiper blades. Commercially available windshield wiper control systems provide an intermittent operational mode wherein the windshield wiper blades will sweep intermittently. Typically, with such commercially available intermittent or time delay windshield wiper control systems, the operator has to continually manually adjust the dwell time (the time between the intermittent sweeps) of the windshield wiper blades in order to adapt to changing conditions. For example, as vehicle speed increases and more rain impacts the windshield, the operator would normally decrease the dwell time. Accordingly, a windshield wiper control systems which automatically compensates for changes in vehicle speed would be desirable. By sensing the vehicle speed, the dwell time can be reduced automatically as the speed increases. The operator no longer has to constantly change this manually. Vehicle speed responsive wiper control systems are known from U.S. Pat. No. 4,881,019, issued in 1989 to Siraishi et al, from U.S. Pat. No. 4,419,611, issued in 1983 to Kawasaki et al and from U.S. Pat. No. 5,017,847, issued in 1991 to Leistenschneider. However, none of these prior art systems takes advantage of the capabilities of microprocessor technology. Since microprocessors are increasingly available on modern vehicles to perform various other functions, it would be desirable to have a vehicle speed responsive intermittent wiper control system which takes advantage of microprocessor technology.